Hood for rock drills



Feb. 8, 1938. L. 0. SMITH 2,107,552

HOOD FOR ROCK DRILLS Filed Sept. 1, 1937.

Patented Feb. 8, 1938 2,101,552 noon roa aoox DRILLS' Lester C. Smith, West Hartford, Coma, assignor to The Spencer Turbine Company, Hartford, Conn., a corporation of Connecticut Application September 1, 1937, Serial No. 161,972

4 Claims.

My invention relates to the class of apparatus that is commonly employed for drilling holes in rock, and an object of my invention, among others, is the production of a shield or hood by means of which dust produced in drilling operations is satisfactorily removed from the air surrounding such operations.

One form of a device embodying my invention and in the construction and use of which the objects herein set out, as well as others, may be attained is illustrated in the accompanying drawing in which Figure 1 is a side view of a pneumatic drill equippedwith my improved device and showing its method of operation.

Figure 2 is a view in central lengthwise section through the device, the scale being enlarged over that shown in Figure 1, the skirt not being collapsed.

Figure 3 is an end view looking into the mouth of the hood.

Figure 4 isa view similar to Fig. 2 but on reduced scale and showing the drill and hood in operating position.

In the accompanying drawing the numeral 5 denotes a tripod in general upon which the drilling apparatus is supported and which, briefly stated, consists of a pneumatic cylinder 6, a feed device 1, and a holding cylinder 8 by means of 0 which the hood is held in place against the face or breast 9 of a mass of rock [0.

In drilling operations in which pneumatic drills are commonly employed it is essential and the law occasionally requires that the dust produced by the drill in suchoperations shall be removed so that the air will not be impregnated with the dust and will not therefore be inhaled by the persons conducting the drilling operations or working in proximity thereto. By the use of my improved device these results are readily attained, such device comprising a hood through which the drill projects and which is held securely in place against the breast of the rock being drilled and surrounding the hole being produced,

such hood comprising a shell I l preferably round and composed of any suitable material as metal. A flange l2 extends around one edge of the case and a cover I3 is secured to said flange said cover being composed preferably of rubber, leather,

or other durable, flexible material. A hole It is formed through the cover through which a drill l5 extends into a well Hi being created by the drill in the rock ID. A spout l! is formed preferably integrally with the shell I I, said spout being smaller in diameter than the shell and having a bell-shaped connection IS with the shell, I as shown in Fig. 2 of the drawing. Openings [9 are formed through the bell into an outlet chamber 20 within the-shell.

A skirt 2i is secured to a flange 22 projecting I from one edge of the shell ll as by means of a clamping band 23 of any suitable construction. Said skirt is preferably composed of rubber and is of corrugated form comprising ribs and grooves 24 and 25, respectively, on its outer surface which I. produce similar ribs and grooves on the inner surface. The material of which this skirt is formed is preferably somewhat thick so that it will have some rigidity while at the same time having yielding qualities sufllcient to enable the a mouth of the spout I! to be pressed against the face or breast of the rock and held in such position as by means of the action of the piston within the holding cylinder 8. The stiifness of the material will be such as to retain the edge 26 of go the skirt securely against the face of the rock.

In other words it will be stifl enough to resume its normal position as shown in Fig. 2 when pressure is removed from it but it will yield to permit the hood to rest upon the edge of the spout. as

A tubular projection 21 extends from one side of the case, as shown in Figs. 1 and" 2, this being suitable for attachment of a tube 28 extending from any suitable suction apparatus by means of which the dust within the hood is removed 30 and conveyed to any suitable receptacle, usually in the form of a separator.

In the operation of the device the hood is held securely against the face or breast of the rock as shown in Figs. 1 and 4, in this position the skirt 2| being collapsed sufliciently to permit the edge 29 of the spout I! to rest firmly against the face of the rock, the device being held in this position by action of the piston within the holding cylinder 8, and in a manner that will be to readily understood. Most of the dust created by action of the drill in the well It will be drawn by suction from the well It through the spout l1 and out through the projection 21 and tube 28. As more or less of an opening will exist between the edge 29 of the spout l1 and the face of the rock, owing to unevenness of the latter, any dust which enters the annular chamber 30 between the skirt 2| and the spout I! will pass 50 through the openings l9 into the outlet chamber 20 and will commingle with the volume of dust passing through the spout l1 and be drawn out of the device in a manner that will be readily understood. 55

I claim: l

1. -A drill hood including a shell closed at one end creating an outlet chamber, a spout smaller in diameter than said shell projecting from the opposite end of said shell and having openings into said outlet chamber; a skirt projecting from said shell and surrounding said spout creating an annular chamber communicating with said openings, and an outlet from said outlet chamber.

2. A drill hood including a shell closed at one end creating an outlet chamber, a spout smaller in diameter than said shell projecting from the opposite end of the shell and having a bell-shaped connection with said shell with openings through said bell-shaped formation into said outlet chamber, a skirt projecting from said shell and surrounding said spout creating an annular chamber communicating with said openings, and an outlet from said outlet chamber.

3. A drill hood including a shell closed at one end creating an outlet chamber, a spout smaller in diameter than said shell projecting from 1 opposite end and having openings into said outlet chamber, a skirt projecting from said shell and surrounding said spout creating an annular chamber communicating with said openina, said skirt being corrugated and of sufllcient to maintain an extended position, and an outlet from said outlet chamber.

4. A drill hood including a shell closed at one end creating an outlet chamber, a spout in diameter than said shell projecting from its opposite end and having an opening into said outlet chamber, said spout having aflared connection with said shell and havfiig opening: through said flared connection, a skirt projecting from said shell and surrounding said spout creating an annular inlet chamber communicating with said openings, said skirt being of sumcient thickness to maintain an extended position, and. an outlet from said outlet chamber.

IESTERQSMITH. 

